the eye Flashcards
what is the path that light takes when it travels through the eye?
cornea –> pupil—> lens —> retina—> optic nerve
what does the eye do to light energy?
changes it into electrical energy
what is the function of the cornea?
refracts light onto the retina
what is the function of the iris?
it is coloured and controls the size of the pupil and the amount of light entering the eye.
what is the function of the retina?
an inner sensitive layer, contains rod cells and cone cells
what are rod cells and where are they found?
rod cells are found in the retina and and work in dim light.
what happens to the pupil in dim light?
the pupil dilates to allow more light into the eye.
what happens to the pupil in light?
pupil constricts and gets smaller.
What happens to the circular and radial muscles in dim light?
the circular muscles with relax and the radial muscles contract. These muscles work antagonistically.
what happens to the circular and radial muscles in light?
the circular muscles will contract and the radial muscles will relax. These muscles work antagonistically.
what happens when the eye is exposed to a light from a far distance?
the ciliary muscles relax and the suspensory ligaments pull of the lens to make it thin and wide.
what happens to the eye when exposed to a light from a near object?
the ciliary muscles contract and the suspensory ligaments become loose which makes the lens into a fatter shape.
what is the function of the conjunctiva?
thin clear protective layer over the surface of the eye and lining the eyelids
what is the function of the ciliary muscle?
changes the thickness of the lens when focusing
whats is the function of the lens?
can change its shape to focus light onto the retina.
what is the function of the sclera?
tough, white protective layer. has many blood vessels which supply the retina with food and oxygen.
what are cone cells and where are they found?
cone cells detect colour and detail and are found in the retina.
what is the most sensitive part of the retina and what does it do?
the fovea, it only contains cones.
what is the blind spot?
the point at where the optic nerve attaches to the eye. there are no light sensitive cells here (no retina)
what is the optic nerve?
carries nerve impulses away to the brain.
